Can Anyone Tell Me If A 91 7.4l Merc 454/b1 Has A Hydro Roller Or A Flat Tappit Cam??

A 91 would be a Mark IV, making it a hydraulic lifter cam.
I dont think the rollers were used in the 454 until Gen VI, 1996?

Thanks, I Guess I Will Know Soon After I Tear Into It.
The Plan Is Aluminum 502 Heads, 502 Cam, Exsaust,intake, 750 Holley,and Msd. This Should Get Me To 480 500hp.just Want To Get My Ducks In Arow So I Can Get The Job Done In A Few Days. Dont Want To Start And Find Out That I Dont Have What I Need And Wait A Week For It To Get Here.

Definately a flat tappet if it is original.